maven——项目构建和依赖管理工具
apache maven是一个用于项目构建和依赖管理的工具。
添加archetype
https://repo1.maven.org/maven2/archetype-catalog.xml
更改本地仓库存储位置：修改配置文件${user.home}/.m2/settings.xml或 $MAVEN_HOME/conf/setting.xml中的内容
<localRepository>...
mvn archetype:generate会非常慢，搜索了本地和远程太多archetype，而加上-DarchetypeCatalog=local将只搜索${user.home}/.m2/archetype-catalog.xml中定义的本地archetype，会大大提高速度。
mvn archetype:crawl会根据远程数据生成本地archetype目录$maven_localRepository/archetype-catalog.xml。
download jar, sources, javadoc
mvn dependency:get -Dartifact=groupId:artifactId:version[:packaging[:classifier]]
eg. mvn dependency:get -Dartifact=mysql:mysql-connector-java:LATEST
mvn dependency:get -Dartifact=mysql:mysql-connector-java:LATEST:jar:sources
download sources/javadoc
mvn dependency:sources -DincludeGroupIds=grouId1,groupId2... -Dclassifier=sources
mvn dependency:get -Dartifact=mysql:mysql-connector-java:LATEST:jar:sources
download sources for each of dependencies in pom.xml
mvn dependency:sources
mvn dependency:resolve -Dclassifier=sources
download javadoc
mvn dependency:get -Dartifact=mysql:mysql-connector-java:LATEST:jar:javadoc
# download javadoc for each of dependencies in pom.xml
mvn dependency:sources -Dclassifier=javadoc
mvn dependency:resolve -Dclassifier=javadoc
copy dependecies
mvn dependency:copy -Dartifact=g:a:v -o -DrepoUrl=file://path/to/your/repo
mvn org.apache.maven.plugins:maven-dependency-plugin:2.8:copy -Dartifact=groupId:artifactId:version[:packaging][:classifier] -DoutputDirectory=[target]
mvn dependency:build-classpath [-Dmdep.outputFile=/path/file]（输出到文件）
mvn基本的几个jar包相关命令：
mvn clean 清除target/编译文件夹
mvn compile 编译源码
mvn package 编译并打包为jar文件
mvn install 将jar文件安装到本地repo
mvn deploy 根据pom.xml中的信息，将jar包部署到远程repo
跳过测试
mvn -DskipTests
指定pom文件
mvn -f some-pom.xml
插件描述文档
mvn help:describe -Ddetail -Dplugin=<plugin-name> 或 -Dcmd=<plugin>:<phase>
# mvn help:describe -Dplugin=exec
# mvn help:describe -Dcmd=install:install-file
# mvn help:describe -Dplugin=g:a:v
关闭mvn的日志输出
mvn -q
生成源码jar包
mvn source:jar
maven 3.x super pom位置
$M2_HOME/lib/maven-model-builder-3.x.jar:/org/apache/maven/model/pom-4.0.0.xml
######## unresolved #########
list addable dependencies in local repository
list addable dependencies all available repositories
list achetypes
（不可用）get file path of artifact
mvn dependency:location -Dartifact=g🅰️v
生成javadoc.jar接口文档包
mvn javadoc:jar
需要添加plugin: org.apache.maven.plugins:maven-javadoc-plugin
生成sources.jar源码包
mvn source:jar
需要添加plugin: org.apache.maven.plugins:maven-source-plugin
mvn命令发布到nexus私服
mvn deploy
如果需要同时发布sources.jar, javadoc.jar，需在生成这些包后执行命令。
执行命令需要pom中有<distributionManagement/repository|snapshotRepository>的配置，同时maven公有settings.xml中<servers/server>下配置nexus私服登录的用户名密码。
<!-- pom.xml -->
<distributionManagement>
<repository>
<id>my-mvn</id> <!-- 必须与settings.xml中定义的id一致 -->
<!--为hosted服务类型的地址，否则400错误，另外，部署一个已存在的jar包也会400 -->
<url>http://exmaples.com/nexus/content/repositories/releases/</url>
</repository>
<snapshotRepository>
<id>my-mvn</id>
<url>http://exmaples.com/nexus/content/repositories/snapshots/</url>
</snapshotRepository>
</distributionManagement>
<!-- maven settings.xml -->
<servers>
<server>
<id>my-mvn</id>
<username>admin</username>
<password>secret-pwd</password>
</server>
</servers>
<!-- 发布源码包/文档包时依赖的plugin -->
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-source-plugin</artifactId>
<version>3.0.0</version>
<executions>
<execution>
<goals>
<goal>jar</goal>
</goals>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-javadoc-plugin</artifactId>
<version>3.0.0</version>
<executions>
<execution>
<goals>
<goal>jar</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
删除损坏jar包
remove damaged jars.
网络条件恶劣会导致下载的jar是不完整的或者损坏的(corrupted)，而添加这种jar包的依赖会导致读取到不正确的class（加了jar包却找不到对应class），此时我们需要找出本地maven库中损坏的jar，然后删除它们，重新下载，命令行脚本：
cd $M2_REPO;
for f in `find -type f -iname '*.jar' -printf '%P\n'`; do unzip -tq "$f" &>/dev/null; [[ $? -ne 0 ]] && echo "$f" | tee -a ~/corruptedmvnjar ; done;
cd -
打包mave项目及其依赖
一般建议用功能更丰富的shade插件，而非assembly。
编译出错
仔细看输出ERROR日志，如提示某个类miss，除了看是否添加了该类的依赖，scop是否对应以外，还需看这个类所在依赖是否使用了其他依赖，而其他依赖却没有添加，或者版本不兼容。
打包到nexus：
pom.xml
<distributionManagement>
<snapshotRepository>
<id>ossrh</id>
<name>Sonatype Nexus Snapshots</name>
<url>https://oss.sonatype.org/content/repositories/snapshots/</url>
</snapshotRepository>
<repository>
<id>ossrh</id>
<name>Nexus Release Repository</name>
<url>https://oss.sonatype.org/service/local/staging/deploy/maven2/</url>
</repository>
</distributionManagement>
增量复制maven库
cd $M2_REPO
zip -r -u ~/Downloads/mvnrepo.zip * # 可加选项排除部分大ja包
maven仓库镜像
添加仓库镜像，解决下载慢的问题
<!--阿里云-->
<mirror>
<id>alimaven</id>
<name>aliyun maven</name>
<url>http://maven.aliyun.com/nexus/content/groups/public/</url>
<mirrorOf>central</mirrorOf>
</mirror>
<!--华为云-->
<mirror>
<id>huaweicloud</id>
<!--官方将这里的mirrorOf设为*，会导致私库不可用-->
<mirrorOf>central</mirrorOf>
<url>https://mirrors.huaweicloud.com/repository/maven/</url>
</mirror>
<!--华为云镜像登录信息-->
<server>
<id>huaweicloud</id>
<username>anonymous</username>
<password>devcloud</password>
</server>
镜像会拦截所有通往被镜像的请求。因此若镜像更新不及时，导致镜像中没有本已存在于被镜像repo（如maven central）的artifact时，mvn下载会失败。
maven私有库
添加私有库 settings.xml
<profile>
<id>...</id>
<repositories>...
<pluginRe...>
</profile>
maven项目添加自己提供的jar：
修改plugin默认版本
修改文件$M2_HOME/lib/maven-core-xxx.jar!:/META-INF/plexus/components.xml及default-bindings.xml中对应plugin的版本
maven java
pom.xml中最常用的设置jdk、项目文件编码的代码如下：
<properties>
<!--设置java源码版本-->
<maven.compiler.source>1.8<maven.compiler.source>
<!--设置字节码版本-->
<maven.compiler.target>1.8<maven.compiler.target>
<!--在maven-compiler-plugin:3.8以后支持jdk9+，设置maven.compiler.release，同时显式设置maven-compiler-plugin的版本为3.8或更高-->
<maven.compiler.release>11</maven.compiler.release>
<!--如果在<build/plugins>显式配置了<artifactId>maven-compiler-plugin</artifactId>中的<execution>，则上述通过propert指定java版本的方式不再起作用，需在<execution/configuration>中配置<source>,<target>-->
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
maven scala
<project>
<!--repo&pluginRepo不是非得添加-->
<repositories>
<repository>
<id>scala-tools.org</id>
<name>Scala-Tools Maven2 Repository</name>
<url>http://scala-tools.org/repo-releases</url>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>scala-tools.org</id>
<name>Scala-Tools Maven2 Repository</name>
<url>http://scala-tools.org/repo-releases</url>
</pluginRepository>
</pluginRepositories>
<dependencies>
<dependency>
<groupId>org.scala-lang</groupId>
<artifactId>scala-library</artifactId>
<version>${scala.version}</version>
</dependency>
</dependencies>
<build>
<plugins>
<!-- maven-scala-plugin非官方出品，已迁移到以下gav -->
<plugin>
<groupId>net.alchim31.maven</groupId>
<artifactId>scala-maven-plugin</artifactId>
<executions>
<execution>
<id>scala-compile-first</id>
<phase>process-resources</phase>
<goals>
<goal>add-source</goal>
<goal>compile</goal>
</goals>
</execution>
<execution>
<id>scala-test-compile</id>
<phase>process-test-resources</phase>
<goals>
<goal>testCompile</goal>
</goals>
</execution>
</executions>
</plugin>
<!--加java编译器-->
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.7.0</version>
</plugin>
<!--<plugin>
<groupId>org.scala-tools</groupId>
<artifactId>maven-scala-plugin</artifactId>
<executions>
<execution>
<goals>
<goal>compile</goal>
<goal>testCompile</goal>
</goals>
</execution>
</executions>
<configuration>
<scalaVersion>${scala.version}</scalaVersion>
<mainSourceDir>src/main/scala</mainSourceDir>
<testSourceDir>src/test/scala</testSourceDir>
</configuration>
</plugin>-->
</plugins>
</build>
</project>
kotlin maven
<properties>
<!--增量编译-->
<kotlin.compiler.incremental>true</kotlin.compiler.incremental>
</properties>
<dependency>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-stdlib</artifactId>
<!--使用jdk特定版本扩展-->
<!--<artifactId>kotlin-stdlib-jre8</artifactId>-->
<!--<artifactId>kotlin-stdlib-jre7</artifactId>-->
<version>${kotlin.version}</version>
</dependency>
<!--kotlin reflect反射相关-->
<dependency>
<artifactId>kotlin-reflect</artifactId>
</dependency>
shade-plugin:
<plugin>
<artifactId>maven-shade-plugin</artifactId>
<version>3.1.0</version>
<configuration>
<!--别生成dependency-reduced-pom.xml文件-->
<createDependencyReducedPom>false</createDependencyReducedPom>
</configuration>
<executions>
<execution>
<!-- 加入package和goal:shade，否则mvn shade:shade不允许直接从命令行执行，加此可直接mvn package -->
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<transformers>
<!--将同名资源文件整合成一个-->
<transformer
implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
<resource>application.properties</resource>
</transformer>
<!-- 定义manifest中main类 -->
<transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
<mainClass>com.examples.AppMain</mainClass>
<manifestEntries><!--manifest文件中的款项配置-->
<Class-Path>xxx</Class-Path>
</manifestEntries>
</transformer>
</transformers>
<!-- 以下排除依赖包中的*.SF *.DSA *.RSA文件，避免运行jar包时报告关于signature不匹配的安全问题 -->
<filters>
<filter>
<artifact>*:*</artifact>
<excludes>
<exclude>META-INF/*.SF</exclude>
<exclude>META-INF/*.DSA</exclude>
<exclude>META-INF/*.RSA</exclude>
</excludes>
</filter>
</filters>
</configuration>
</execution>
</executions>
</plugin>
